Agitating apparatus for flocculating treatment of suspensions



Feb. 24, 1970 w M. JABLON AGITATING APPARATUS FOR FLOCCULATING TREATMENT OF SUSPENSIONS 2 Sheets-Sheet 1 Filed Aug. 14, 1968 Feb. 24, 1970 T. M. JABLON 3,497,184

AGITATING APPARATUS FOR FLOCCULATING TREATMENT OF SUSPENSIbNS Filed Aug 14, 1968 2 Sheets-Sheet 2 'INVENTOR.

' QZ MMZM US. Cl. 259-100 United States Patent Office 3,497,184 Patented Feb. 24, 1970 ABSTRACT OF THE DISCLOSURE This invention relates to the fiocculating treatment of the suspension of solids or turbidity in liquids, in a horizontal throughfiow tank, by way of gentle agitation, and more particularly to improvements in the type of agitating mechanism wherein a horizontally extending flexible assembly of agitating means is endwise suspended in catenary fashion, and the assembly is moved up and down in a liquid body in the tank, featuring a parallel draft cable system.

The liquid or suspensions to be treated in the apparatus of this invention may, for example, comprise raw providing conveniently operable means for adjusting and determining the desired catenary shape.

The invention therefore lies in the provision of a draft cable system for motivating the swingable frames in synchronism from a single drive shaft rotatable alternatingly in opposite directions, wherein a first draft cable means leads from the single drive shaft to the first or adjacent supporting frame, while a second draft cable means operating in parallel to the first draft cable means leads from the shaft to the second or distant supporting frame. The effective length of each of these draft cable means may bglvariable, thereby rendering the catenary shape adjusta e.

In one preferred embodiment, a single drive shaft ac tuates a pair of similar agitating apparatus, each featuring the above outlined draft cable system, in such a manner that movements of the one agitating apparatus is water, sewage, trade waste or' any suspension wherein it is desired to flocculate these solids through the operation of a suitable agitating mechanism in a fiocculating tank, with or without the aid of fiocculating chemicals.

More particularly, this invention is concerned with improving the agitating mechanism that operates in a horizontal throughfiow tank of the type disclosed in US. patent to Lindell No. 3,164,379. Improvements upon the apparatus of the Lindell patent are disclosed in the patent to Williamson et al. No. 3,389,892 of June 25, 1968.

Both Lindell and Williamson disclose agitating mechanism wherein a bank of ribbon elements are endwise suspended from a pair of swingable frames which move the ribbon elements up and down in the body of liquid in the tank, producing the desired type of agitation.

The Williamson application, in addition, discloses stress relief cable means inter-connecting the lower ends of these frame structures, which cable means are shorter than the catenaries of the agitator bands. A horizontal actuating shaft extending across the top of the tank has a draft cable attached to the lower end up one of the swinging frames in such a manner that rotating the shaft in one direction will swing this one frame structure upwardly while transmitting similar swinging movement through the stress relief cables to the other frame structure, thereby causing r both frame structures to move substantially in synchronism while providing stress relief for the catenaries of the agitator bands and preserving a desired catenary shape. The' length of the horizontal stress relief cables may be adjustable, whereby the shape or sag of the catenary is adjustable. Rotating of the shaft in the opposite direction will lower the assembly of agitating elements.

However, as these frame structures reach the end of their upward swinging movement, stress in the horizontal relief cables inter-connectingthe' frames reaches a maximum, possibly to the extent of several times the operating stress encountered during the initial part of the lifting movement. These peak stresses translate themselves into corresponding peak stresses in the bearings of the swinging frames.

One object of the invention is to provide eflicient actuating mechanism for moving the frame structures in syn chronism. This mechanism should provide stress relief for the flexible assembly of the agitating elements, without the' need of the highly stressed horizontal relief cables, and should eliminate the peak pressures in the bearings by substituting uniformly low bearing pressures, even while balanced relative to the movement of the other.

Other features and advantages will hereinafter appear.

As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the inven tion is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims, or of forms that are their functional as well as conjointly cooperative equivalents, are therefore intended to be embraced by those claims.

FIG. 1 is a plan view of the fiocculating apparatus embodying this invention, showing agitating elements of the ribbon type in a flexible assembly.-

FIG. 2 is a longitudinal or sectional view of the ap paratus, taken on line 2-2 of FIG. 1.

FIG. 3 shows the apparatus of FIG. 1 in duplex arrangement actuated from a common drive,

FIG. 4 is a partial plan view taken on line 44 of FIG. 3, showing the common drive shaft for the' duplex arrangement.

FIG. 5 illustrates another type of flexible assembly of agitating elements adapted for use in this invention.

In the example herein shown to illustrate the invention, the agitating apparatus in the flocuulating tank resembles the one shown in the Williamson patent in respect to the use of a bank of parallel ribbons as agitating elements, but differs from that disclosure by the provision of separate draft cables for moving the swinging frame structures in synchronism directly from a common actuating shaft.

In the present example, the fiocculating mechanism is installed in a horizontal throughfiow treatment tank 10 of rectangular elongate shape having a fiat bottom 11, side walls 12 and 13, influent end 14 and an eflluent end 15.

The fiocculating apparatus itself in this example comprises a bank of parallel flexible agitator elements or bands 16 having loop-shaped terminals 17 and 18 whereby they are hingedly connected to the lower ends or transverse rods 18a of respective swingable supporting frames 19 and 20.

Each of the agitator elements in this example may consist of a flexible band of stainless steel of very small thickness as compared to its width, for example, a band of material having a thickness of .010 to .020 inch and a width of perhaps 2 to 4 inches.

The swingable support frames depending into the liquid body in the tank are movable about parallel axes extending across the tank. Each support frame itself is a rigid structure swingable in a pair of bearings 21 and 22 mounted upon respective side walls of the tank. These frames may have transverse bars or slats 23 providing rigidity as well as agitation.

The actuating means for raising and lowering this assembly comprise an actuating shaft 28 parallel to the axes of frame 20, and spaced, a horizontal distance D1 therefrom towards the adjacent end of the tank. The

reversible drive motor 31 is operable to rotate the shaft alternatingly i'n'opposite directions. This shaft is mounted in bearings 29 and 30, and carries fixed thereon a pair of winding drums 26 and 27. A first pair of parallel draft cables 24 and 25 connect the respective drums 27 and 26 with the lower end of the adjacent frame structure 20.

Means foradjusting the length of these'draft cables may be provided in the form of turn buckles T. a

Furthermore, fixed'uponthis drive shaft are a second pair of winding drums 26a and 27a to operate the second pair of draft cables 24a' and 25a'connected to the lower end of the distant frame structure 19, which draft cables are guided over respective pulleys 32 and 33 mounted on a shaft 34 extending across the tank and parallel to the actuating shaft 28. Additional guide means 35 may be provided for the horizontal portion of draft cables 24a and 25a. Again, the length of these lon ger draft being substantially similar to the one described above in FIGS. land 2.

The first flexible assembly 40 is endwise supported by two swingable frames 42 and 43, while the second assembly 41 is supported by two swinging frames 44 and 45.

In this duplex arrangement, the up-and-down movements of the two flexible assemblies are effectively interbalan ced' through the operation of the shaft, in a manner whereby.

the drive torque requirements are minimized.

Accordingly, for actuating the one assembly 40, the shaft carries a pair of winding drums 46 and 47, operating a pair of parallel drive cables 48 and 49 connected to the lower endof the adjacent frame structure 42. An-- other pair of windingdrums 50 and 51 on the shaft controls the winding and unwinding of another pair of parallel draft cables 52 and 53 connected to the lower end of the distant frame structure 43, with pulleys 43a providing the required guidance'Rotation of the shaft alternatingly in both directions will raise or lower the assembly 40 due to the synchronized movements of the frame structures imparted thereto through the respective draft cables extending separately from shaft 38.

The other flexible assembly 41 is endwise suspended from the swingable frame structures 44 and 45. These frame structures are moved in synchronism due to the provision of a pair of winding drums 56 and 57 on the shaft, with parallel-draft cables 58 and 59 connecting them to the lower end of the adjacent frame structure 44. Another pair of winding drums 60 and 61 on the shaft operates parallel draft cables 62 and 63 connected to the lower end of the distant framestructure with pulleys 63a providing the required guidance for these cables. Rotation of shaft 38 will move the frame structure of this assembly in synchronism, thusraising and lowering the assembly 41;

As seen from FIG. 3, rotation of the shaft is so controlled as to move the two assemblies 40 and 41 up and down in alternation, providing interbalance or weight compensation.

FIG. 5 illustrates another form of a flexible assembly of agitating elements which may be substituted for the bank of ribbon elements shown in FIGS. 1 and 2. In this example, .the agitating elementsproper are in the form of rigid agitator bars or members 64, arranged in parallel spaced relationship to one another. These agitator elements extend transversely 'of a pair of flexible linear supporting elements or ropes 65, to which they are adjustably fastened as by suitable clamping devices or the like not shown. These supporting ropesv in turn are endwise supported in catenary fashion from respective depending swingable frame structures 66 and 67 which may be similar to those shown and describedabove in connection with the embodiments of FIGS. 1 to 3.'Inthis example the flexible'assemblyhas a terminal loop 68 at each corner, which loops are readily attachable to, and detachable from pins 69 projecting laterally from the lower ends of the respective frames.

It will be understood that each of the elements or two or: more .together, of the apparatus herein described,

may also find application in agitator mechanism other than the type described above.

Furthermore, while the invention'has been illustrated and described as embodied in a flocculating agitating mechanism comprising a pair of swingable frames supporting a flexible assembly of agitating means, and draft cable means formoving the frames in synchronism, de- 3:

signed to minimize the 'catenary stresses in the flexible assembly, as well as other stresses resulting therefrom, it is not intended to be limited to the details shown, since various modifications and structural as well as functional changes may be made without departing from the i spirit of the present invention.

1. In a horizontal throughflow type of liquid treatment tank, an agitating apparatus which comprises a first frame structure mountedfor swinging movementiabout a horizontal axis and extending from said axis into the liquid body in the tank,

a second frame structure mounted for'swinging movementabout a horizontal axisparallel to and horizontally spaced a substantial distance from said first horizontal axis and extending downwardly from its f axis into the liquid body in the tank;

a flexible substantially horizontal assembly of agitating elements, p

hinge devices connecting the ends of said assembly to respective frame structures at points located a substantial distance from the respective horizontal axes thereof, whereby said assembly is suspended in catenary fashion, and may be moved up and down when swinging said frame structuresin unison,

a drive shaft parallel to the axesof said frame structures, and located outside the distanceseparating said axes, and spaced a horizontal distance away from the axis of said one frame structure in the direction of upward movement of said frame structures,

first draft cable means having. one end connected to said shaft, and the other end connected to the one N adjacent frame structure at a point spaced a substantial distance from the axis thereof,

second draft cable means having one end connected to said shaft, and the other'end connected to the other frame structure in'a manner similar to the connection of said first cable means to the'first frame structure, said second and said first draft cable 5 6 3. The apparatus according to claim 1, with the addi- References Cited tion of a second agitating apparatus similar to the one UNITED STATES PATENTS defined in claim 1, so arranged that all axes of all frame 7 structures are parallel to one another and to said shaft, 3,015,476 1/ 1952 st'uart 259100 X and wherein the draft cable means of said second agitat- 3,164,379 1/ 1965 Lllldell 259100 ing apparatus are connected to said shaft in such a 5 3,389,892 6/1968 Wlnlamson 259100 manner that the movements of both said agitating apparatus are balanced with respect to each other. ROBERT JENKINS Pnmary Examiner 4. The apparatus according to claim 3, wherein said two agitating apparatus are disposed opposite each other,

and said shaft is located intermediate said two apparatus. 10 259 4 

